An energy management system (EMS) is a system of computer implemented tools used by operators of electric utility grids to monitor, control, and optimize the performance of the generation and/or transmission of an energy delivery system. In other words, an EMS is used to optimize, supervise and control the transmission grid, generation assets, and in some cases, the loads. The monitoring and control functions are known as “supervisory control and data acquisition” (SCADA). Control of such a system can involve autonomous automatic control actions by the EMS to arrest deviations in power system frequency whenever imbalances arise between load and generation.
One tool that utilities have to help more cost-effectively control load is called Demand Response (DR). According to the Federal Energy Regulatory Commission, DR is defined as changes in electric usage by end-use customers from their normal consumption patterns in response to changes in the price of electricity over time, or to incentive payments designed to induce lower electricity use at times of high wholesale market prices or when system reliability is jeopardized, DR includes all intentional modifications to consumption patterns of electricity to induce customers that are intended to alter the timing, level of instantaneous demand, or the total electricity consumption. DR programs are designed to decrease electricity consumption or shift it from on-peak to off-peak, periods depending on consumers' preferences and lifestyles. Demand response activities are defined as “actions voluntarily taken by a consumer to adjust the amount or timing of his energy consumption”. Actions are generally in response to an economic signal (e.g., energy price, or government and/or utility incentive). Demand response is a reduction in demand designed to reduce peak demand or avoid system emergencies. Hence, demand response can be a more cost-effective alternative than adding generation capabilities to meet the peak and/or occasional demand spikes. The underlying objective of DR is to actively engage customers in modifying their consumption in response to pricing signals. The goal is to reflect supply expectations through consumer price signals or controls and enable dynamic changes in consumption relative to price.
In electricity grids, DR is similar to dynamic demand mechanisms to manage customer consumption of electricity in response to supply conditions, for example, having electricity customers reduce their consumption at critical times or in response to market prices. The difference is that demand response mechanisms respond to explicit requests to shut-off, whereas dynamic demand devices passively shut off when stress in the grid is sensed. Demand response can involve actually curtailing power used or by starting on-site generation which may or may not be connected in parallel with the grid. This is a quite different concept from energy efficiency, which means using less power to perform the same tasks, on a continuous basis or whenever that task is performed. At the same time, demand response is a component of smart energy demand, which also includes energy efficiency, home and building energy management, distributed renewable resources, and electric vehicle charging.
Current demand response management systems (DRMS) are implemented with large and small industrial and commercial as well as residential customers, often through the use of dedicated control systems to shed loads in response to a request by a utility or market price conditions. For example, services (e.g., lights, machines, air conditioning, water heaters) are reduced according to a preplanned load prioritization scheme during a planned time frame. An alternative to load shedding is on-site generation of electricity to supplement the power grid. Under conditions of tight electricity supply, DR can significantly decrease the peak price and, in general, electricity price volatility.
A DRMS provides functionality for the operation and settlement of DR programs. A user is able to schedule the distribution of DR events using a DRMS interface when a DR program is needed (i.e., the DR program is “called”). In some embodiments, an event can additionally be automatically triggered (e.g., programmatically) based on specified conditions, not requiring any interaction with a user interface. The DRMS sends DR event signals to controllable end devices, such as water heaters, thermostats, and switches through an Advanced Metering Infrastructure (AMI), RCS, or a DR gateway (e.g., such as an OpenADR device) installed at the participant's site. The DRMS calculates the settlement data, which is the basis for the DR incentive payment to the participant used for billing. Settlement occurs after the DR event when meter data is available in the Meter Data Management (MDM) system.
Managing the myriad of continually changing participant loads that can be shed or consumed/shifted during a DR event presents a challenging administrative problem with substantial overhead. Thus, there is a significant need to provide systems, methods and apparatus for improved aggregation of participant sites in a demand response management system.